In many cases, surgery must be performed on the heart. Under most circumstances, the heart is stopped while this surgery is performed, and the patient is kept alive during surgery through the use of a so-called “heart-lung machine”. This type of surgery is frequently referred to as “on pump” surgery.
However, it has been recognized that the use of a heart-lung machine can have serious deleterious effects on the patient. Therefore, interest has become widespread in conducting so-called “off pump”, or “beating heart”, coronary artery bypass surgery. In this type of procedure, the bypass surgery is conducted while the patient's heart continues to beat. While this type of surgery can be significantly more difficult for the surgeon, the advantages can also be sufficiently great for the patient. As a result, a substantial percentage of bypass procedures are now done off pump.
However, for some types of procedures, e.g., aortic valve replacement, it can be effectively impossible to conduct the required surgery off pump using conventional apparatus and methods.
However, in pending PCT Patent Application No. PCT/US00/02126, filed Jan. 27, 2000 by Viacor Incorporated for CARDIAC VALVE PROCEDURE METHODS AND DEVICES, which patent application is hereby incorporated herein by reference, there is disclosed a novel apparatus and method for conducting off pump aortic valve replacement. In this patent application there is disclosed, among other things, apparatus comprising a temporary valve and filter which is placed in the aorta downstream from the defective aortic valve and which can effectively replace the functionality of the defective aortic valve while that valve is resected and replaced, and which also prevents debris from the valve resection from passing downstream during the resection procedure.
One object of the present invention is to provide a novel apparatus and method for providing improved protection for the coronary arteries during valve resection.
Another object of the present invention is to provide a novel apparatus and method for providing improved coronary perfusion during valve resection.
Another object of the present invention is to provide, in a single apparatus, used through a single point of entry, (1) a check valve for ensuring unidirectional flow of blood from the heart to the circulatory system, (2) filtration mechanisms for preventing debris from passing down the coronary arteries and/or the aorta, (3) apparatus to augment coronary perfusion, and (4) apparatus for passing instruments from the incision site to the heart.